From mboxrd@z Thu Jan  1 00:00:00 1970
X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me
X-Spam-Level: 
X-Spam-Status: No, score=-2.9 required=5.0 tests=BAYES_00,FREEMAIL_FROM,
	MAILING_LIST_MULTI autolearn=unavailable autolearn_force=no
	version=3.4.4
X-Google-Thread: 103376,703c4f68db81387d
X-Google-Attributes: gid103376,public
X-Google-Language: ENGLISH,ASCII-7-bit
Path: 
 g2news1.google.com!news4.google.com!newsfeed2.dallas1.level3.net!news.level3.com!bloom-beacon.mit.edu!npeer.de.kpn-eurorings.net!news.agarik.com!usenet-fr.net!enst.fr!melchior!cuivre.fr.eu.org!melchior.frmug.org!not-for-mail
From: Marius Amado Alves <amado.alves@netcabo.pt>
Newsgroups: comp.lang.ada
Subject: Magic ordering
Date: Tue, 15 Mar 2005 12:54:30 +0000
Organization: Cuivre, Argent, Or
Message-ID: <mailman.27.1110891298.23655.comp.lang.ada@ada-france.org>
References: <4229bad9$0$1019$afc38c87@news.optusnet.com.au>
	<1110032222.447846.167060@g14g2000cwa.googlegroups.com>
	<871xau9nlh.fsf@insalien.org>
	<3SjWd.103128$Vf.3969241@news000.worldonline.dk>
	<87r7iu85lf.fsf@insalien.org> <1110052142.832650@athnrd02>
	<42309456$1@news.broadpark.no> <ow2Yd.21162$7U5.4617@fe04.lga>
	<opsnfw9nx75afhvo@localhost> <d0qiah$ep71@cui1.lmms.lmco.com>
	<pan.2005.03.11.18.01.45.684764@linuxchip.demon.co.uk.uk.uk>
	<d0sob3$3t5$1@s1.news.oleane.net>
	<4232ab3a$0$26547$9b4e6d93@newsread4.arcor-online.net>
	<pan.2005.03.14.14.41.47.813082@linuxchip.demon.co.uk.uk.uk>
	<d14co1$ca4$1@s1.news.oleane.net>
	<pan.2005.03.14.17.16.34.592520@linuxchip.demon.co.uk.uk.uk>
	<tnpZd.3116$qN3.2240@trndny01>
	<pan.2005.03.15.00.10.18.647492@linuxchip.demon.co.uk.uk.uk>
	<1110888090.283361.113590@z14g2000cwz.googlegroups.com>
NNTP-Posting-Host: lovelace.ada-france.org
Mime-Version: 1.0 (Apple Message framework v619.2)
Content-Type: text/plain; charset=US-ASCII; format=flowed
Content-Transfer-Encoding: 7bit
X-Trace: melchior.cuivre.fr.eu.org 1110891299 6676 212.85.156.195 (15 Mar 2005
 12:54:59 GMT)
X-Complaints-To: usenet@melchior.cuivre.fr.eu.org
NNTP-Posting-Date: Tue, 15 Mar 2005 12:54:59 +0000 (UTC)
Cc: comp.lang.ada@ada-france.org
To: "Hans Malherbe" <hans.malherbe@gmail.com>
Return-Path: <amado.alves@netcabo.pt>
In-Reply-To: <1110888090.283361.113590@z14g2000cwz.googlegroups.com>
X-Mailer: Apple Mail (2.619.2)
X-OriginalArrivalTime: 15 Mar 2005 12:54:34.0911 (UTC)
	FILETIME=[237EE2F0:01C5295E]
X-Virus-Scanned: by amavisd-new-20030616-p10 (Debian) at ada-france.org
X-BeenThere: comp.lang.ada@ada-france.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: "Gateway to the comp.lang.ada Usenet newsgroup"
	<comp.lang.ada.ada-france.org>
List-Unsubscribe: <http://www.ada-france.org/mailman/listinfo/comp.lang.ada>,
	<mailto:comp.lang.ada-request@ada-france.org?subject=unsubscribe>
List-Post: <mailto:comp.lang.ada@ada-france.org>
List-Help: <mailto:comp.lang.ada-request@ada-france.org?subject=help>
List-Subscribe: <http://www.ada-france.org/mailman/listinfo/comp.lang.ada>,
	<mailto:comp.lang.ada-request@ada-france.org?subject=subscribe>
Xref: g2news1.google.com comp.lang.ada:9436
Date: 2005-03-15T12:54:30+00:00

(Sorry I changed the subject. I'm just that kind of guy :-)

On 15 Mar 2005, at 12:01, Hans Malherbe wrote:

> I have to ask myself though: If I am denied access to information that
> lets me  implement a < operator, am I supposed to be able to sort it?

This is one of my favourites. There's always a way. Bit by bit 
comparison, an arbitrary index, 'Address comparison...

I'm the guilty part for Ada.Containers supplying a default hash 
function for some types (Strings I think). I also fought for a magic 
ordering function, and to extend both to all types, or at least to a 
vaster class, but I lost.